Powerless helical locking mechanism for door

ABSTRACT

A powerless helical locking mechanism for door includes a screw ( 1 ) with variable lead angle connected with a power ( 11 ) and a self-adaptive nut ( 19 ) connected to the door ( 10 ), in which, the helical flux of the screw is divided into three segments: one segment is a working segment with the helical lead angle greater than the friction angle, one segment is a closing segment with the helical lead angle smaller than the friction angle, and transition segment between the two segments, the power ( 11 ) actuates the screw to corotation and reverse, the self-adaptive nut ( 19 ) consists a spindle sleeve ( 7 ), a wrist ( 5 ) and other part, the nut and the screw is assembled to a helical kinematic-pair, wherein the wrist is dipped into the helical flutes of the screw and line contacts with the flute making the wrist and random helical flute of helical lead angle form mating helical pair to translate power and movement.

FIELD OF THE INVENTION

The present invention belongs to mechanical driving field, relates to a locking and self-unlocking mechanism for powerless helix-driven door machines.

BACKGROUND OF THE INVENTION

The helix-driven door machines are widely used, such as in various vehicle doors, shielding doors, and civil doors and so on. The helix-driven door machines usually have problems on locking and unlocking. At present, both home and abroad helix-driven door machines usually adopt various locks formed by brakes and clutches or the locks with electromagnetic, hydraulic and pneumatic driving modes for locking and unlocking. Most of the door machine locking devices mentioned above have the disadvantages of complicated mechanism and low reliability theri unlocking usually requires additional power sources,

SUMMARY OF THE INVENTION

The present invention is aimed to solve the defects mentioned above, put forward a simple and reliable powerless helical locking mechanism for door, to realize the locking and powerless self-unlocking of helix-driven door machine. Its technical solution is: a powerless helical locking mechanism for door, consists of a screw with variable lead angle, and a self-adaptive nut; the screw with variable lead angle is connected with the power source, and the self-adaptive nut is connected with the door; the screw slot of the screw with variable lead angle is divided into three sections: working section with the lead angle more than the friction angle, locking section with the lead angle less than the friction angle, and transition section between them; the power source can drive the screw with variable lead angle to rotate bidirectionally; the self-adaptive nut is composed by connected shaft sleeve and pin shaft and so on, the self-adaptive nut is assembled with the screw with variable lead angle into the screw kinematic pair, the pin shaft in the self-adaptive nut shall be deep into the screw slot of the screw with variable lead angle and realize the linear contact with the screw slot so that the pin shaft and screw slot with any lead angles may form the matched screw pair to realize the power and motion transfer.

Its features are: {circle around (1)} powerless: both the locking and unlocking of door machine don't require additional power source, only the CW and CCW rotations of the screw with variable lead angle and self-adaptive nut themselves may realize the locking and self-unlocking of self-adaptive nut, thus realize the locking and powerless self-unlocking of door; high reliability: at the locking section of the screw with variable lead angle, the lead angle of screw pair is less than the friction angle as cause self-locking and thus let the screw with variable lead angle lockup the self-adaptive nut, that is, securely lockup the door, no unlock problems are caused by vibration etc.; while the power source drives the CW and CCW rotations of the screw with variable lead angle, it also drives the self-adaptive nut and door to move synchronously in parallel with the axis of the screw with variable lead angle, with the self-adaptive nut entering and exiting the locking section of the screw with variable lead angle to realize the lock and powerless self-unlock of door machine. {circle around (2)} simple: the door lock mechanism has less parts and simple structure. The present invention is suitable for various helix-driven door machine locks.

Working Principle of the Present Invention

When the power source closes the door, the screw with variable lead angle makes the CW rotation and drives the self-adaptive nut to move from its working section to its locking section, once the self-adaptive out enters the locking section of the screw with variable lead angle, the close of the door is realized, and then the automatic locking of the door is realized;

When the power source opens the door, the screw with variable lead angle makes the CCW rotation and drives the self-adaptive nut to move from its locking section to its working section, once the self-adaptive nut withdraws from the locking section of the screw with variable lead angle, the automatic unlock of door is realized, then the open of the door is realized;

When close the door with hands, the difference from closing the door with power source is that the self-adaptive nut may drive the screw with variable lead angle to rotate and let the self-adaptive nut enter the locking section of the screw with variable lead angle to realize the automatic locking of the door and fulfill the close of the door;

When open the door with hands, just design a device to let the screw with variable lead angle make the CCW rotation of a specific angle, the self-adaptive nut withdraws from the locking section of the screw with variable lead angle and unlocking is realized, then the open of the door is realized by the CCW motion of self-adaptive nut, the shift lever, gear, clutch unlocking devices and many other devices may be applied for this purpose

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is working principle drawing of the present invention.

FIG. 2 is partial enlargement view of typical section of the screw with variable lead angle 1.

FIG. 3 is the perspective cross-sectional view of pin shaft of self-adaptive nut 19 at the working section of the screw with variable lead angle 1.

FIG. 4 is the perspective cross-sectional view of pin shaft 5 of self-adaptive nut at the locking section of the screw with variable lead angle 1.

FIG. 5 is the working principle schematic diagram of manual unlocking device.

FIG. 6 is the 3D illustration of FIG. 5.

In FIG. 1-6: 1—the screw with variable lead angle, 2—nut, 3—retainer ring, 4—torsion spring, 5—pin shaft, 6—rolling bearing, 7—spindle sleeve, 8—bearing cap, 9—nut sleeve, 10—door, 11—power source, 12—pull-wire wheel, 13—left shift lever, 14—right shift lever, 15—right connecting plate, 16—pull-wire, 17—torsion spring, 18—middle strut, 19—self-adaptive nut

DETAILED DESCRIPTION OF THE EMBODIMENTS

The followings are the detailed description of the present invention with combination of FIG. 1.

A powerless helical locking mechanism for door, consists of the screw with variable lead angle 1, and self-adaptive nut 19; the screw with variable lead angle 1 is connected with power source 11, the power source can drive the screw with variable lead angle to rotate bidirectionally, and the self-adaptive nut 19 is connected with door 10 as drives the self-adaptive nut 19 and the door to move synchronously. The screw slot of the screw with variable lead angle 1 is divided into three sections: working section with the lead angle more than the friction angle, locking section with the lead angle less than the friction angle, and transition section between them; the screw slot of the screw with variable lead angle has rectangle or trapezoid threaded end face, the screw slot of the screw with variable lead angle may be single head or multiple heads; the self-adaptive nut 19 consists of spindle sleeve 7, pin shaft 5, nut sleeve 9, nut 2, rolling bearing 6 and bearing cap 8, retainer ring 3, and torsion spring 4; the nut 2 and nut sleeve 9 have the circumference rotary connection, and have rigid connection through retainer ring 3 in axis; one end of torsion spring 4 is connected with nut sleeve 9, and the other end is connected with nut 2, the pin shaft and spindle sleeve are connected in rigid connection or rotary connection, when the pin shaft 5 and spindle sleeve 7 are in rigid connection, the screw pair is in sliding friction; when the pin shaft 5 and spindle sleeve 7 are in rotary connection, the screw pair is in rolling friction.

When the power source 11 closes the door, the screw with variable lead angle 1 makes CW rotation to drive the self-adaptive nut 19 to move from the working section of the screw with variable lead angle to locking section, until the self-adaptive nut 19 enters the locking section and the door is locked. When the power source 11 opens the door, the screw with variable lead angle 1 makes CCW rotation to drive the self-adaptive nut 19 to leave the locking section and move reversely to open the door. When manually closes the door, the movement of self-adaptive nut 19 drives the screw with variable lead angle 1 to make CW rotation, let the self-adaptive nut 19 enter the locking section of the screw with variable lead angle to manually close the door and lock the door.

The manual open of the door is shown in FIG. 5. The right shift lever 14 is connected with nut 2 of self-adaptive nut 19 through the right connecting plate 15; the left shift lever 13 is connected with pull wire wheel 12; the pull wire wheel 12 is idly set on the screw with variable lead angle 1; pull wire 16 is connected with pull wire wheel 12; one end of torsion spring 17 is connected with pull wire 16 and the other end is connected with middle strut 18. The pull wire 16 drives the pull wire wheel 12 and left shift lever 13 to rotate and through the right shift lever 14, the right connecting plate 15 drives the nut 2 to rotate to realize the rotation of the screw with variable lead angle 1 to a specific angle, after the manual unlock is completed, open the door by hands with the CCW rotation of self-adaptive out 19. After unlocking, under the torsion of torsion spring 17, the pull wire wheel 12 and pull wire 16 reset to be ready for the next manual unlocking.

FIG. 2 is the partial enlargement view of typical section of screw slot of the screw with variable lead angle 1, wherein, part A is the locking section, with the lead angle less than the friction angle, part C is the working section, with the lead angle more than the friction angle, and part B is the transition section between them, with the lead angle varies continuously.

FIG. 3 is the illustration of pin shaft 5 of self-adaptive nut 19 at the working section of the screw with variable lead angle 1, the self-adaptive nut 19 and the screw with variable lead angle 1 are assembled into a screw kinematic pair, the pin shaft of self-adaptive nut 19 is deep into the screw slot of the screw with variable lead angle 1 and is in linear contact with the screw slot, the pin shaft and screw slot with any lead angles can form the matched screw pair to transfer the power and motion, to realize open and close of the door.

FIG. 4 is the illustration of pin shaft of self-adaptive nut 19 at the locking section of the screw with variable lead angle 1, at the locking section of the screw with variable lead angle 1, with the self-locking caused by that lead angle of screw pair is less than the friction angle, the screw slot of locking section in the screw with variable lead angle 1 can lockup the pin shaft 5, that is, the self-adaptive nut 19 is unable to move, thus reliably locks the door. 

1. A powerless helical locking mechanism for door, consists of screw with variable lead angle and self-adaptive nut; the screw with variable lead angle is connected with the power source, and the self-adaptive nut is connected with the door; the screw slot of the screw with variable lead angle is divided into three sections: working section with the lead angle more than the friction angle, locking section with the lead angle less than the friction angle, and transition section between them; the power source can drive the screw with variable lead angle to rotate bidirectionally; the self-adaptive nut is composed of connected spindle sleeve and pin shaft and other parts, the self-adaptive nut is assembled with the screw with variable lead angle into the screw kinematic pair, the pin shaft in the self-adaptive nut shall be deep into the screw slot of the screw with variable lead angle and in linear contact with the screw slot, the pin shaft and screw slot with any lead angles may form the matched screw pair to realize the power and motion transfer.
 2. A powerless helical locking mechanism for door according to claim 1, wherein the locking section of the screw with variable lead angle is a screw slot with the lead angle not more than the friction angle.
 3. A powerless helical locking mechanism for door according to claim 1, wherein the screw slot of the screw with variable lead angle may be single head or multiple heads
 4. A powerless helical locking mechanism for door according to claim 1, wherein the pin shaft and spindle sleeve may adopt either rigid or rotary connection. 